Pharmacology (Seminar)

Question 1

What is pharmacodynamics?

Answer 1

How the drug affects the body.

Question 2

What is pharmcokinetics?

Answer 2

What the body does to the drug, involves ADME precesses =

• absorption.
• distribution.
• metabolism.
• excretion.

Question 3

State 4 mode of actions for drugs (how they achieve their effects)?

Answer 3

1) . Receptors.
2) . Enzymes.
3) . Ion Channels.
4) . Transporters.

Question 4

What does agonist mean?

Answer 4

Activates the receptor to produce a response.

• substance binds to an receptor which causes an effect.

Question 5

What does antagonist mean?

Answer 5

Binds to the receptor and blocks the endogenous ligand.

• preventing its effects.

Question 6

What factors affect the absorption of an oral drug across the GI tract?

Answer 6

1) . How quickly the tablet dissolves.
2) . pH of stomach contents, food, other drugs.
3) . Physiological factors =
- how quickly the drug is moved through the GI tract, e.g. diarrhoea.

Question 7

What factors affect the distribution of a drug?

Answer 7

• Blood flow to target organs.
• Health of the liver.
• Blood pressure.
• Protein binding.

Question 8

What happens to the drug in the liver?

Answer 8

1) . Drug is broken down, ready to be excreted by the kidneys.
2) . It gets metabolised by enzymes (becomes inactive).

Question 9

What is bioavailability?

Answer 9

The proportion of drug which reaches the circulation system.

Question 10

Will a drug that undergoes extensive first pass metabolism have low or high bioavailability?

Answer 10

LOW

• because it’s been substantially broken down by the liver before it reaches the general circulation.

Question 11

Digoxin is a drug which undergoes little metabolism and is mainly eliminated through renal excretion. What would happen to the plasma levels of digoxin in a patient with renal impairment?

Answer 11

• Half-life = longer.
• Levels = would increase.
• Increasing risk of digoxin toxicity.

Question 12

What does it mean if a drug has a narrow therapeutic margin?

Answer 12

Difference between a toxic dose and a sub-therapeutic dose is small.

Question 13

Name a drug originally sourced from a plant?

Answer 13

• Digoxin.
• Morphine.
• Aspirin.

Question 14

Name a drug originally sourced from an animal?

Answer 14

Insulin.

Question 15

Name a drug originally sourced from a mineral?

Answer 15

Calcium carbonate.

Question 16

Name which drugs aren’t administered orally?

Answer 16

All EXCEPT;

• gentamicin.
• glyceryl trinitrate.
• insulin.

Question 17

Name a drug that is administered through the nose (inhaled)?

Answer 17

Salbutamol.

Question 18

Name an orally administered drug which isn’t absorbed from the GI tract?

Answer 18

Lactulose –> inactivated in the liver.

Question 19

Name an orally administered drug that doesn’t usually cross the blood barrier?

Answer 19

Cetirizine (antihistamine which does not usually cause drowsiness).

Question 20

Name an orally administered drug that is active when metabolised by the body?

Answer 20

Levodopa (in the brain metabolised to dopamine).

Question 21

Name a drug which has a narrow therapeutic margin?

Answer 21

• Digoxin.
• Gentamicin.
• Theophyline.

Question 22

Name a drug that would be completely metabolised (inactivated) by the liver if taken orally?

Answer 22

Glyceryl trinitrate.

Question 23

Name a drug that is renally excreted and would need extra care in the elderly (lower dose)?

Answer 23

• Digoxin.

- Penicillin.

Question 24

Name a drug which acts as a receptor agonist?

Answer 24

• Salbutamol.

- Morphine.

Question 25

Name a drug which acts as an enzyme inhibitor?

Answer 25

• Ibuprofen.
• Aspirin.
• Theophylline.

Question 26

Name a drug which acts on reuptake transporters?

Answer 26

Citalopram.